Fluid transfer assembly

ABSTRACT

A fluid transfer assembly for transferring a fluid between an onshore or offshore installation and a tanker, includes a floating device provided with positioning means for maintaining a predetermined position, a first fluid transfer line for releasably connecting said onshore or offshore installation to said floating device, and a second fluid transfer line for releasably connecting said floating device to the tanker. The floating device is provided with a connecting device for establishing a fluid connection between the first and second fluid transfer lines, which connecting device and floating device are separate parts that can be joined and separated by cooperating couplers provided on the connecting device and floating device, respectively, without compromising the original function of the floating device.

CROSS-REFERENCE TO RELATED APPLICATION

The present application is a national stage filing of Internationalpatent application Serial No. PCT/EP2007/061285, filed Oct. 22, 2007,and published as WO 2009/052853 in English.

BACKGROUND

The discussion below is merely provided for general backgroundinformation and is not intended to be used as an aid in determining thescope of the claimed subject matter.

A fluid transfer assembly is used for transferring a fluid between anonshore or offshore installation and a tanker.

For example, such a fluid transfer assembly is used to transfer oil orgas from an offshore production installation towards a tanker.

SUMMARY

This Summary and the Abstract herein are provided to introduce aselection of concepts in a simplified form that are further describedbelow in the Detailed Description. This Summary and the Abstract are notintended to identify key features or essential features of the claimedsubject matter, nor are they intended to be used as an aid indetermining the scope of the claimed subject matter. The claimed subjectmatter is not limited to implementations that solve any or alldisadvantages noted in the background.

Thus, in accordance with a first aspect of the invention, the fluidtransfer assembly comprises a floating device provided with positioningdevice for maintaining a predetermined position; a first fluid transferline for releasably connecting said onshore or offshore installation tosaid floating device, and a second fluid transfer line for releasablyconnecting said floating device to the tanker, wherein the floatingdevice is provided with a connecting device for establishing a fluidconnection between the first and second fluid transfer lines, whichconnecting device and floating device are separate parts that can bejoined and separated by a cooperating coupler provided on the connectingdevice and floating device, respectively, without compromising theoriginal function of the floating device.

The connecting device and floating device being separate parts allowsthe use of non-dedicated floating devices (in contrast to floatingdevices specifically designed for such a task, such as for examplevessels provided with a turret, turntable and/or moonpool) incombination with the connecting device. For example, when severe damagehas occurred to existing state of the art fluid transfer assemblies dueto extreme weather conditions (e.g. hurricanes) the fluid transfercapability from an offshore oil or gas field towards a tanker (or shore)may be (re)-established quickly by coupling a connecting device with afloating device (for example a towboat, platform supply vessel or anchorhandling vessel) at hand at said specific location.

In one embodiment the connecting device comprises an intermediate fluidtransfer line mounted in a frame, said intermediate fluid transfer linehaving a first end provided with a first connector for cooperation witha corresponding connector of the first fluid transfer line, and having asecond end provided with a second connector for cooperation with acorresponding connector of the second fluid transfer line.

When the connecting device is coupled to the floating device, connectingthe fluid transfer lines thereto allows one to establish the desiredfluid transfer capability in a simple manner.

Further, then, it is preferred in one embodiment that the firstconnector of the connecting device and the corresponding connector ofthe first fluid transfer line define a rotating coupling allowing thefloating device to rotate around said coupling relative to the firstfluid transfer line.

Such a rotating coupling allows the floating device to weathervane suchas to assume a position in which environmental loads (e.g. arising fromcurrent, waves or wind) are minimized, while maintaining the desiredfluid transfer capability. Generally, in such a case, the tanker willmove (rotate) along with the floating device, substantially maintainingits position relative thereto. The rotation may occur without angularlimitation.

When, in accordance with an embodiment of the fluid transfer assemblyaccording to the present invention the connecting device is positionablerelative to the floating device such, that the first and second fluidlines, when connected to the intermediate fluid transfer line, extendoutboard of the floating device, indeed the connecting device may beused in combination with a non-dedicated floating device without theneed of extensively amending or adapting the floating device. Only quitesimple provisions are needed, such as a coupler for cooperation with acoupler of the connecting device. One should realize, however, thatapart from these mechanical couplers also provisions may be present forrealizing a connection for hydraulic power, electrical power etc.

When, in accordance with yet another embodiment, the end of the firstfluid transfer line to be connected to the connecting device is providedwith a buoy member, the first fluid transfer line may be disconnectedfrom the connecting device (whenever the need arises) and may bereconnected easily at a later stage by picking up the buoy memberfloating in the water (it is noted that the buoyancy of the buoy membermay cause the respective end of the first fluid transfer line toactually float on the water, but also may be such that it floats at somedistance below the water surface).

In one embodiment, the positioning device of the floating device cancomprise thrusters. This eliminates the use of anchored mooring lines.

For example the positioner further may comprise a position monitoringsystem (e.g. a gps-based system) providing control signals for thethrusters, thus creating a dynamically positioned arrangement.

Secondly an aspect of the invention relates to a retrofittableconnecting device for application in a fluid transfer assembly. Such aconnecting device comprises an intermediate fluid transfer line, saidintermediate fluid transfer line having a first end provided with afirst connector for cooperation with a corresponding connector of thefirst fluid transfer line, and having a second end provided with asecond connector for cooperation with a corresponding connector of thesecond fluid transfer line, and further comprises a coupler forcooperation with a corresponding coupler on a floating device forjoining and separating the connecting device and said floating device.

Finally an aspect of the invention relates to a kit for establishing afluid transfer connection between an onshore or offshore installationand a tanker. Such a kit comprises a first fluid transfer line with adistal end for connection to said onshore or offshore installation andwith a proximal end, a second fluid transfer line with a distal end forconnection to said tanker and with a proximal end, and a connectingdevice which can be connected releasably to the proximal ends of saidfirst and second fluid transfer lines for establishing a fluidconnection therebetween, which connecting device further can be joinedto and separated from a floating device.

BRIEF DESCRIPTION OF THE DRAWINGS

Aspects of the invention will be elucidated while referring to thedrawing in which

FIG. 1 illustrates schematically an embodiment of a fluid transferassembly used in deep water, in a side elevational view, and

FIG. 2 illustrates, on a larger scale, a schematical perspective view ofa connector.

DETAILED DESCRIPTION OF THE ILLUSTRATIVE EMBODIMENT

Firstly referring to FIG. 1 a fluid transfer assembly is illustrated fortransferring a fluid from an offshore installation (such as for examplean oil production installation 1) to a tanker 2. It is noted thatinstead of an offshore installation also an onshore installation may bepresent as starting point for the transfer of the fluid. Further it isnoted that the tanker 2 may be connected to a towboat for keeping itscorrect position and preloading on a hawser connection (to be describedlater). The tanker 2 also may be used as a facility for temporarilystoring the fluid, alone or in combination with an additional tanker.

A floating device, here a vessel 3, is provided with a positioner 30 formaintaining a predetermined position. In one embodiment, the vessel 3preferably is a non-dedicated vessel, that means a vessel devisedoriginally for a task different from transferring fluid such as forexample a towboat. In the present embodiment the positioner 30 formaintaining a predetermined position are meant for maintaining theposition of the vessel 3 relative to the offshore installation 1; itdoes not mean that the orientation of the vessel 3 is maintained(specifically, as will be elucidated later, the vessel will be able torotate or ‘weathervane’ around a stationary point). In one embodiment,said positioner can comprise thrusters 31 (schematically illustrated)controlled by a position monitoring system 32 (e.g. a gps-based system)and a control system 33.

The assembly further comprises a first fluid transfer line 4 forreleasably connecting said offshore installation 1 to said vessel 3. Inthe illustrated embodiment said first fluid line 4 extends below sealevel 5 and comprises a number of successive sections between buoymembers 6. The buoy members 6 are attached to anchoring lines 7 which,in the illustrated embodiment, are connected to ballast weights 8resting on the sea floor 9. It is noted that it also is conceivable thatthe first fluid transfer line 4 extends at least partially above sealevel 5.

The first fluid transfer line 4 has a distal end connected for a fluidcommunication to the installation 1 in a manner not shown in detail, butknown per se, and an opposite proximal end connected for a fluidcommunication to the vessel 3 in a manner detailed later.

A second fluid transfer line 10 is provided for releasably connectingsaid vessel 3 to the tanker 2. In the illustrated embodiment said secondfluid transfer line 10 is of a type floating on the water surface. Thesecond fluid transfer line 10 has a distal end connected for a fluidcommunication to an appropriate installation on board of the tanker 2 ina manner not shown in detail, but known per se, and an opposite proximalend connected for a fluid communication to the vessel 3 in a mannerdetailed later.

Moreover, as is known per se, a hawser connection 11 connects the vessel3 with the tanker 2. Some devices for manipulating this hawserconnection 11 (such as, for example, a reel) are not shown in detail,but are known per se. The hawser connection 11 may be of aquick-disconnect type and/or be provided with a load monitoring system34 providing signals for the control system of the vessel 3 (e.g. thecontrol system 33 controlling the thrusters 31).

The vessel 3 is provided with a connecting device 12 for establishing afluid connection between the first fluid transfer line 4 and the secondfluid transfer line 10, specifically between the proximal ends thereof.Details of the connecting device will be elucidated below whilereferring to FIG. 2.

The proximal end of the first fluid transfer line 4 to be connected tothe vessel 3 for example with a buoy member 13. In the illustratedembodiment this buoy member 13 is connected to a ballast weight (orother anchoring devices) 14 on the sea floor 9 by means of an anchoringline 15. The buoy member 13 will keep the proximal end of the firstfluid transfer line afloat (or at e pre-determined depth) when detachedfrom the vessel 3 (for example when, due to bad weatherconditions—hurricanes—the vessel 3 and tanker 2 will have to leave thearea), which will enable an easy pick-up of said proximal end at a laterstage for re-instating the connection with the vessel.

Next, reference is made to FIG. 2 which, on a larger scale andschematically, illustrates a possible embodiment of the connectiondevice 12 shown in FIG. 1.

Firstly it should be emphasized that the connecting device 12 and vessel3 (latter not shown in FIG. 2) are separate parts that can be joined andseparated. Separate parts means, therefore, that the connecting device12 can be removed from the vessel 3 without compromising the originalfunction of the vessel 3 (this could mean also, without damaging thevessel 3 and/or connecting device 12). Or in other words, there areprovided couplers on the connecting device 12 and vessel 3,respectively, which allow a repeated connection and disconnection ofboth parts. Such parts are indicated schematically at 16 in FIG. 2.

The connecting device 12 comprises an intermediate fluid transfer line17 mounted in a frame 18. Additional means such as valves, dry break(dis)connectors etc. are not shown in detail, but may be provided too.Said intermediate fluid transfer line 17 has a first end provided with afirst connector 19 for cooperation with a corresponding connector 20 ofthe first fluid transfer line 4, and has a second end provided with asecond connector 21 for cooperation with a corresponding connector ofthe second fluid transfer line 10.

The first connector 19 of the connecting device 12 and the correspondingconnector 20 of the first fluid transfer line 4 define a rotatingcoupling allowing the vessel 3 to rotate ('weathervane') around saidcoupling relative to the first fluid transfer line 4. Referring to whathas been noted previously, one can say that the vessel 3 has astationary position but variable orientation relative to said rotatingcoupling. In other words, the rotating coupling defines a substantiallyvertical axis around which the vessel 3 (and therewith the tanker 2) mayrotate.

Connectors for establishing such a rotating coupling are known per seand are not further elucidated here. They may be quick-disconnectable.

In the illustrated embodiment the second connector 21 of the connectingdevice 12 and the corresponding connector 22 of the second fluidtransfer line 10 define a stationary coupling; however it is conceivabletoo that said coupling also can rotate at least in a limited way. Thesedevices may be quick-disconnectable too.

In the embodiment as illustrated, the frame 18 is provided with alifting assembly herein lifters 23 and 24 for lifting ends of the firstand second fluid transfer lines. Such lifters 23 and 24 (which, forexample, may comprise outriggers 25, a winch and lifting cables) will bedevised for enabling an easy and quick pick-up and, if needed,controlled release of the lines 4 and 10, whatever the case may be. Aseparate frame with winch and power pack also may be used.

The connecting device 12, or specifically its frame 18, is positionablerelative to the vessel 3 such, that the first and second fluid lines 4and 10, when connected to the intermediate fluid transfer line 17,extend outboard of the vessel 3. This may be achieved by means of theoutriggers 25, for example.

A connecting device 12 may be kept in storage (onshore or offshore).When, for instance, an existing fluid export capability has beencompromised or an existing fluid transfer assembly has been damaged (forexample by a hurricane) the connection device 12 can be retrofitted to avessel 3, such as a towboat which needs only minimum adaptations, i.e.couplers 16 for attaching the connecting device 12 to the deck of thevessel 3. As a result the fluid transfer capability can be re-instatedin a quick manner. The fluid transfer assembly thus created may be usedon a temporary basis, but may also be used during a prolonged time.Further its use may be temporarily interrupted (for example formaneuvering the vessel 3 with tanker 2 out of the path of an arrivinghurricane) by disconnecting the first and possibly second fluid transferlines 4, 10 from the connecting device 12. At a later stage areconnection may be established.

However, not only may a connection device 12 as stated above be kept instorage, but also a kit for establishing a fluid transfer connectionbetween an onshore or offshore installation and a tanker 2, comprising afirst fluid transfer line 4, a second fluid transfer line 10, andconnectors 19, 21 which can be connected releasably to the proximal endsof said first and second fluid transfer lines 4, 10 for establishing afluid connection therebetween.

The invention is not limited to the embodiments described before whichmay be varied widely within the scope of the invention as defined by theappending claims. For example, the vessel 3 may have (interim) storagecapabilities. Further it is possible, that the couplings described abovedefine quick-disconnectable couplings, that is couplings that can bedisconnected in a very short time.

The invention claimed is:
 1. A fluid transfer assembly for transferringa fluid between an onshore or offshore installation and a tanker,comprising: a floating device provided with a positioner configured tomaintain a predetermined position; a first fluid transfer line forreleasably connecting said onshore or offshore installation to saidfloating device, and a second fluid transfer line for releasablyconnecting said floating device to the tanker, wherein the floatingdevice is provided with a connecting device having an intermediate fluidtransfer line fixedly mounted to a frame for establishing a fluidconnection between the first and second fluid transfer lines, theintermediate fluid transfer line having two fluidly coupled ends, thefirst and second fluid transfer lines being directly couplable to theends of the intermediate fluid transfer line with quick-disconnectablecouplings, and wherein the connecting device and floating device areseparate parts configured to be joined and separated by cooperatingcouplers provided on the connecting device and floating device,respectively, the connecting device being removable as a unit from thefloating device through the couplers that couple the frame to thefloating device, wherein said ends of said intermediate fluid transferline comprise a first end provided with a first connector forcooperation with a corresponding connector of the first fluid transferline, and a second end provided with a second connector for cooperationwith a corresponding connector of the second fluid transfer line, andwherein the frame is provided with a lifting assembly configured to liftends of the first and second fluid transfer lines.
 2. The fluid transferassembly according to claim 1, wherein the first connector of theconnecting device and the corresponding connector of the first fluidtransfer line define a rotating coupling allowing the floating device torotate around said coupling relative to the first fluid transfer line.3. The fluid transfer assembly according to claim 1, wherein the firstconnector of the connecting device and the corresponding connector ofthe first fluid transfer line define the quick-disconnectable coupling.4. The fluid transfer assembly according to claim 1, wherein the secondconnector of the connecting device and the corresponding connector ofthe second fluid transfer line define a stationary coupling.
 5. Thefluid transfer assembly according to claim 1, wherein the secondconnector of the connecting device and the corresponding connector ofthe second fluid transfer line define the quick-disconnectable coupling.6. The fluid transfer assembly according to claim 1, wherein theconnecting device is positionable relative to the floating device suchthat the first and second fluid transfer lines, when connected to theintermediate fluid transfer line, extend substantially entirely outboardof the floating device.
 7. The fluid transfer assembly according toclaim 1, wherein the end of the first fluid transfer line to beconnected to the connecting device is provided with a buoy member. 8.The fluid transfer assembly according to claim 1, wherein the positionercomprises thrusters and a position monitoring system providing controlsignals for the thrusters.
 9. The fluid transfer assembly according toclaim 1, wherein the connecting device and floating device areconfigured to be joined and separated by the cooperating couplerswithout compromising the original function of the floating device. 10.The fluid transfer assembly according to claim 1, further comprising ahawser connection between the floating device and the tanker.
 11. Thefluid transfer assembly according to claim 10, wherein the hawserconnection is provided with a load monitoring system for monitoring thestress load on the hawser connection.
 12. The fluid transfer assemblyaccording to claim 10, wherein the hawser connection isquick-disconnectable.
 13. A retrofittable connecting device forapplication in a fluid transfer assembly, comprising: a frame; anintermediate fluid transfer line fixedly mounted to the frame, saidintermediate fluid transfer line having a first end provided with afirst connector for cooperation with a corresponding connector of afirst fluid transfer line, and having a second end provided with asecond connector for cooperation with a corresponding connector of asecond fluid transfer line, wherein the first connector and thecorresponding connector of the first fluid transfer line and the secondconnector and the corresponding connector of the second fluid transferline each comprise a quick- disconnectable coupling; couplers forcooperation with corresponding couplers on a floating device for joiningand separating the connecting device and said floating device, theconnecting device being removable as a unit from the floating devicethrough the couplers that couple the frame to the floating device; andwherein the corresponding connectors of the first and second fluidtransfer lines are directly couplable to the first and second ends ofthe intermediate fluid transfer lines, and wherein the frame is providedwith a lifting assembly configured to lift ends of the first and secondfluid transfer lines.
 14. The connecting device according to claim 13,wherein the first connector is configured to define a rotating couplingwith the corresponding connector of the first fluid transfer lineallowing the floating device to rotate around said coupling relative tothe first fluid transfer line.
 15. The connecting device according toclaim 13, wherein the second connector is configured to define astationary coupling with the corresponding connector of the second fluidtransfer line.
 16. The connecting device according to claim 13, whereinthe connecting device is positionable relative to the floating devicesuch that the first and second fluid transfer lines, when connected tothe intermediate fluid transfer line, extend entirely outboard of thefloating device.
 17. A connecting device for establishing a fluidtransfer connection between an onshore or offshore installation and atanker, the connecting device configured to be connected withquick-disconnectable couplings releasably to proximal ends of fluidtransfer lines for establishing a fluid connection therebetween, whichconnecting device further is configured to be joined to and separatedfrom a floating device, the connecting device comprising couplersconfigured to secure the connecting device to the floating device suchthat substantially all the weight of the connecting device is supportedby the floating device; an intermediate fluid transfer line having firstand second ends provided with first and second connectors, respectively,for cooperation with corresponding connectors of the fluid transferlines, respectively; a first fluid transfer line with a distal end forconnection to said onshore or offshore installation and with a proximalend having a connector connected to the first connector; a second fluidtransfer line with a distal end for connection to said tanker and with aproximal end having a connector connected to the second connector; and alifting assembly configured to lift ends of the first and second fluidtransfer lines.
 18. The connecting device according to claim 17, whereinthe intermediate fluid transfer line is mounted in a frame and whereinsaid frame is provided with the couplers for cooperation withcorresponding couplers on said floating device such that substantiallyall the weight of the connecting device is supported through the frame.19. The connecting device according to claim 17, wherein the firstconnector and the corresponding connector of the first fluid transferline define a rotating coupling allowing the connecting device to rotatearound said coupling relative to the first fluid transfer line.